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I am using the U-type tinnerman fasteners on my cowl:
http://www.aircraftspruce.com/catalog/h ... kkey=62675

I have been using stainless steel machine screws to screw into them. But the tinnermans are eating up the threads on the machine screws. I only get 1 or 2 uses out of the screws and then they have to be thrown away. Do I need some other kind of screw, or is there a softer version of these tinnermans?

Mike Smith

Mike,
I have never seen machine screws used with tinnermans. The 140 used them extensively but always with sheet metal screws.

Well, then that might be the explanation. Machine screws have much tighter threads than sheet metal screws. I must have missed that in my A&P class. Oh, wait a minute. I never went to A&P school. Explains a lot ;-)

Mike